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<head>
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    <title>何芳-圆</title>
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<body>
    <input type="text" name="" id="" placeholder="请输入半径"><br>
    <input type="text" name="" id="" placeholder="周长" ><br>
    <input type="text" name="" id="" placeholder="面积"><br>
    <input type="button" value="确定">
    <input type="button" value="重置">
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